Preload and flv doesn't work on Firefox


We’ve created this interactive for a Cd-rom. Now we are trying to implement it to internet and are facing some problems.
We were testing it in Internet Explorer and all works well.
But the client in testing it in Firefox and in fact the preloads are skipped and the videos don’t load.
The videos are loaded into an FLVPlayback from a external folder. I’m using Flash 8.

You may take a look at it in here:

Or, if the client decides to put it active on-line, here: